nope. no flux is required at all, wiikey might need flux for the pad (or just rosin core solder) but for wii there is already solder on the pads so you really dont need any flux or flux core solder also you need very little solder if any (enough solder on the wii already for install if 30awg is used)

*Edit*
if you have paste or liquid flux you can use it on wiikey pad, also dip the exposed wire into the flux then apply solder, it will get tinned really well.

The only tools I had was a bbq skewer, a soldering iron (i filed down the tip), a small vile of soldering tin (not sure if that's what it's called [just some cheap shit like THIS]) and a few wires i raped from a broken walkman.

Anyway, I really had no clue what I was doing, so i just cut a teeny bit of soldering tin off and melted it onto some wire. It solidifies really quickly, so you can just put the wire up. So now you have a wire with a little bead of solder on it and you just point it on the pad you want to solder it onto and you melt it directly onto the pcb.

I admit, there is probably a WAYYY better way of doing this... I almost botched it FIVE times!?!?! At one stage, two of the pads were connected and i had to melt and chissel. It was damn scary..

AAAAAnyway.... an hour later, i'm playing a burnt copy of super paper mario on a PAL wii